Asked by meg
How many grams of CH3COOH are needed to make 4.2 liters of aqueous solution of pH=3.4?Be sure to back correct from equilibrium molecular acid molarity to starting molecular acid molarity.
Answers
Answered by
DrBob222
I can tell you how to solve the problem BUT I have no idea what your second sentence says.
CH3COOH is a weak acid, therefore, one must determine CH3COOH from the Ka and the known H3O^+.
CH3COOH + H2O ==> H3O^+ + CH3COO^-
Ka = (H3O^+)(CH3COO^-)/(CH3COOH)
If pH = 3.4, use pH = -log(H3O^+) to solve for (H3O^+). Plug that into the Ka expression for (H3O^+) and for (CH3COO^-)
For (CH3COOH), plug in X-(H3O^+) and solve for X. That will give you the molarity of CH3COOH you need for that pH.
You want 4.2L so moles CH3COOH needed will be M x L.
moles = grams/molar mass. Solve for grams.
CH3COOH is a weak acid, therefore, one must determine CH3COOH from the Ka and the known H3O^+.
CH3COOH + H2O ==> H3O^+ + CH3COO^-
Ka = (H3O^+)(CH3COO^-)/(CH3COOH)
If pH = 3.4, use pH = -log(H3O^+) to solve for (H3O^+). Plug that into the Ka expression for (H3O^+) and for (CH3COO^-)
For (CH3COOH), plug in X-(H3O^+) and solve for X. That will give you the molarity of CH3COOH you need for that pH.
You want 4.2L so moles CH3COOH needed will be M x L.
moles = grams/molar mass. Solve for grams.
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.